Our aim is to understand in molecular terms the behavior, i.e. the regulation of motility, of a relatively simple organism, Paramecium tetraurelia. This unicellular ciliated eucaryote combines the advantages of microbes for genetic and biochemical studies with the advantages of large size for electrophysiology and cell biology. The genetics and behavior of existing mutants will be further characterized and we will isolate new types of mutants, including ion-resistants and ion-oversensitives, as well as revertants from the existing mutants. Fluxes of Ca ions or Ba ions through ion channels and pumps will be studied in cilia and ciliary membrane vesicles. We will use electrophoretic techniques to compare the membrane proteins of wild type and behavioral mutants to establish which proteins are involved in the ion fluxes which regulate swimming behavior. We will purify specific membrane proteins and prepare antibodies against them to be used as tools in exploring the cellular location and function of the proteins. We will continue our studies of membrane protein phosphorylation and will look also at membrane protein methylation to determine whether these covalent alterations play a role in adaptation. Cytoplasms from different strains will be transferred to various mutants by conjugation or microinjection to test the possibility that certain ion-gating functions of the membrane require diffusible factors, as suggested by recent literature. If such factors are demonstrated, we will fractionate wild-type cytoplasm to identify them. We will also examine cytochemically the possible ATPase activity at the base of the central pair of microtubules in the cilia of wild type and several mutants. The hypothesis that Ca-induced contraction of the kinetodesmal fibers in the mechanism of ciliary reversal will be tested.